"Astronomy Domine" is a song by English rock band Pink Floyd. The song, written and composed by original vocalist/guitarist Syd Barrett, was the first track featured on their debut album, The Piper at the Gates of Dawn (1967). The lead vocal was sung by Barrett and keyboard player Richard Wright. Its working title was "Astronomy Domine (An Astral Chant)". "Domine" (the vocative of "Lord" in Latin) is a word frequently used in Gregorian chants.